[Gmsh] Gmsh - High order node misplaced

[Anthony Gee]

Hello,


I'm Anthony Gee. I am using gmsh 3.0.6 to generate nodes for high order interpolation. I found some odd behavior when meshing a sphere with cubic and higher 2D elements. I can only observe this from the exported .msh file with ASCII 2.0. Somehow, one or more of the elements include an internal node that should be in a different element. I've attached a picture of one such element. The blue points are the nodes of one element from the .msh file for a sphere with ~8000 cubic elements. The orange point is the central node and shows the misplaced node for that element. I have observed this with higher order and more elements but lower order or less elements seems ok.


I'm not sure why this occurs or whether it shows up in other structures. I could not find a fix in the geometry or meshing options. I've attached my .geo and .msh file. For this case, I generated the 2D mesh and only used refine by splitting command a few times to get 8192 triangles. Please let me know if I made a mistake somewhere. Thank you.


Anthony Gee
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